Iron availability from meat

1978 ◽  
Vol 39 (3) ◽  
pp. 631-638 ◽  
Author(s):  
T. Hazell ◽  
D. A. Ledward ◽  
R. J. Neale
Keyword(s):  
Molecular Weight ◽  
Degradation Products ◽  
Gel Filtration ◽  
Rat Muscle ◽  
Muscle Extract ◽  
Freeze Dried ◽  
Absorption Studies ◽  
Fe Complexes

1. The distribution of radioactive iron in59Fe-labelled rat muscle extract was determined using ge filtration. This showed that most (approximately 70%) of the radioactivity was associated with the heamatin compounds; myoglobin and haemoglobin.2. Raw beef and freeze-dried rat muscle were digested in vitro, under simulated physiological conditions, and after centrifugation the supernatants fractionated by gel filtration. The soluble products were haematin Fe complexes of molecular weight above 10 000 and non-haematin Fe compounds of molecular weight below 6000, the major products being the non-haematin Fe complexes. The soluble compounds were also separated by dialysis and, in rat muscle, it was found that the low-molecular-weight non-haematin compounds accounted for more than 80% of the total soluble iron.3. In vivo absorption studies with rats showed the Fe in a digested muscle dialysate to be more readily absorbed than that from an aqueous muscle extract which itself was more readily absorbed than the Fe from whole blood.4. It may not, therefore, be the haemoproteins per se which are responsible for the high availability of Fe in meat, but rather the nature of their degradation products, formed by digestion within the meat environment.

HEMODIALYSIS OF THE RAT

1966 ◽  
Vol 44 (5) ◽  
pp. 849-859 ◽  
Author(s):  
Sumner M. Robinson ◽  
David A. Hurwitz ◽  
Robert Louis-Ferdinand ◽  
William F. Blatt
Keyword(s):  
Molecular Weight ◽  
Gel Filtration ◽  
Low Molecular Weight

A technique is described for hemodialysis of either anesthetized or non-restrained rats. In the apparatus the dialysis plates of an autoanalyzer system are used with only minor modification. The efficiency of this method has been evaluated with regard to the clearance of saccharides, both in vitro and in vivo, as well as the extraction of nitrogenous low molecular weight moieties from circulating blood. Approximately 50% of the dialyzable material was obtained in a 1-hour dialysis. Further fractionation of the dialyzate was accomplished by gel filtration (Sephadex G-25).

scholarly journals Isolation and Characterization of Two Proteins fromMoraxella catarrhalis That Bear a Common Epitope

1998 ◽  
Vol 66 (9) ◽  
pp. 4374-4381 ◽  
Author(s):  
John C. McMichael ◽  
Michael J. Fiske ◽  
Ross A. Fredenburg ◽  
Deb N. Chakravarti ◽  
Karl R. VanDerMeid ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Bacterial Attachment ◽  
Vaccine Candidates ◽  
Isolation And Characterization ◽  
Sds Page

ABSTRACT The UspA1 and UspA2 proteins of Moraxella catarrhalisare potential vaccine candidates for preventing disease caused by this organism. We have characterized both proteins and evaluated their vaccine potential using both in vitro and in vivo assays. Both proteins were purified from the O35E isolate by Triton X-100 extraction, followed by ion-exchange and hydroxyapatite chromatography. Analysis of the sequences of internal peptides, prepared by enzymatic and chemical cleavage of the proteins, revealed that UspA1 and UspA2 exhibited distinct structural differences but shared a common sequence including an epitope recognized by the monoclonal antibody 17C7. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), purified UspA1 exhibited a molecular weight of approximately 350,000 when unheated and a molecular weight of 100,000 after being heated for 10 min at 100°C. In contrast, purified UspA2 exhibited an apparent molecular weight of 240,000 by SDS-PAGE that did not change with the length of time of heating. Their sizes as determined by gel filtration were 1,150,000 and 830,000 for UspA1 and UspA2, respectively. Preliminary results indicate the proteins have separate functions in bacterial pathogenesis. Purified UspA1 was found to bind HEp-2 cells, and sera against UspA1, but not against UspA2, blocked binding of the O35E isolate to the HEp-2 cells. UspA1 also bound fibronectin and appears to have a role in bacterial attachment. Purified UspA2, however, did not bind fibronectin but had an affinity for vitronectin. Both proteins elicited bactericidal antibodies in mice to homologous and heterologous disease isolates. Finally, mice immunized with each of the proteins, followed by pulmonary challenge with either the homologous or a heterologous isolate, cleared the bacteria more rapidly than mock-immunized mice. These results suggest that UspA1 and UspA2 serve different virulence functions and that both are promising vaccine candidates.

scholarly journals Solubility and ADMET profiles of short oligomers of lactic acid

ADMET & DMPK ◽  
2020 ◽  
Author(s):  
Daniela Dascălu ◽  
Diana Larisa Roman ◽  
Madalina Filip ◽  
Alecu Aurel Ciorsac ◽  
Vasile Ostafe ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Glucocorticoid Receptors ◽  
Degradation Products ◽  
Organic Anion ◽  
Toxicity Tests ◽  
Medical Applications ◽  
Eye Injuries ◽  
Toxicological Effects

<p class="ADMETkeywordsheading">Polylactic acid (PLA) is a polymer with an increased potential to be used in different medical applications, including tissue engineering and drug-carries. The use of PLA in medical applications implies the evaluation of the human organism's response to the polymer inserting and to its degradation products. Consequently, within this study, we have investigated the solubility and ADMET profiles of the short oligomers (having the molecular weight lower than 3000 Da) resulting in degradation products of PLA. There is a linear decrease of the molar solubility of investigated oligomers with molecular weight. The results that are obtained also reveal that short oligomers of PLA have promising pharmacological profiles and limited toxicological effects on humans. These oligomers are predicted as potential inhibitors of the organic anion transporting peptides OATP1B1 and OATP1B3, they present minor probability to affect the androgen and glucocorticoid receptors, have a weak potential of hepatotoxicity, and may produce eye injuries. These outcomes may be used to guide or to supplement in vitro and/or in vivo toxicity tests such as to enhance the biodegradation properties of the biopolymer.</p>

scholarly journals Characterization of proteins from the cytoskeleton of Giardia lamblia

1983 ◽  
Vol 59 (1) ◽  
pp. 81-103 ◽  
Author(s):  
R. Crossley ◽  
D.V. Holberton
Keyword(s):  
Molecular Weight ◽  
Sodium Dodecyl Sulphate ◽  
Giardia Lamblia ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Molecular Size ◽  
Molecular Weights

Proteins from the axonemes and disc cytoskeleton of Giardia lamblia have been examined by sodium dodecyl sulphate/polyacrylamide gel electrophoresis. In addition to tubulin and the 30 X 10(3) molecular weight disc protein, at least 18 minor components copurify with the two major proteins in Triton-insoluble structures. The most prominent minor bands have the apparent molecular weights of 110 X 10(3), 95 X 10(3) and 81 X 10(3). Protein of 30 X 10(3) molecular weight accounts for about 20% of organelle protein on gels. In continuous 25 mM-Tris-glycine buffer it migrates mostly as a close-spaced doublet of polypeptides, which are here given the name giardins. Giardia tubulin and giardin have been purified by gel filtration chromatography in the presence of sodium dodecyl sulphate. Well-separated fractions were obtained that could be further characterized. Both proteins are heterogeneous when examined by isoelectric focusing. Five tubulin chains were detected by PAGE Blue 83 dye-binding after focusing in a broad-range ampholyte gel. Giardin is slightly less acidic than tubulin. On gels it splits into four major and four minor chains with isoelectric points in the pI range from 5.8 to 6.2. The amino acid composition of the giardin fraction has been determined, and compared to Giardia tubulin and a rat brain tubulin standard. Giardins are rich in helix-forming residues, particularly leucine. They have a low content of proline and glycine; therefore they may have extensive alpha-helical regions and be rod-shaped. As integral proteins of disc microribbons, giardins in vivo associate closely with tubulin. The properties of giardins indicate that in a number of respects - molecular size, charge, stoichiometry - their structural interaction with tubulin assemblies will be different from other tubulin-accessory protein copolymers studied in vitro.

scholarly journals A Validated HPLC-PDA-HRMS Method to Investigate the Biological Stability and Metabolism of Antiparasitic Triterpenic Esters

Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7154
Author(s):  
Laura Schioppa ◽  
Fanta Fall ◽  
Sergio Ortiz ◽  
Jacques H. Poupaert ◽  
Joelle Quetin-Leclercq
Keyword(s):  
Medicinal Plants ◽  
Degradation Products ◽  
Biological Stability ◽  
Acidic Media ◽  
Microsomal Metabolism ◽  
Plasma Enzymes ◽  
Absorption Studies ◽  
H 30

Pentacyclic triterpenes (PTs) are commonly found in medicinal plants with well-known antiparasitic effects. Previous research on C-3 and C-27 triterpenic esters showed effective and selective in vitro antiparasitic activities and in vivo effectiveness by parenteral routes. The aim of this study was to determine triterpenic esters’ stability in different biological-like media and the main microsomal degradation products. An HPLC-PDA method was developed and validated to simultaneously analyze and quantify bioactive triterpenic esters in methanol (LOQ: 2.5 and 1.25–100 µg/mL) and plasma (LOQ: 5–125 µg/mL). Overall, both triterpenic esters showed a stable profile in aqueous and buffered solutions as well as in entire plasma, suggesting gaining access to the ester function is difficult for plasma enzymes. Conversely, after 1 h, 30% esters degradation in acidic media was observed with potential different hydrolysis mechanisms. C-3 (15 and 150 µM) and C-27 esters (150 µM) showed a relatively low hepatic microsomal metabolism (<23%) after 1 h, which was significantly higher in the lowest concentration of C-27 esters (15 µM) (>40% degradation). Metabolic HPLC-PDA-HRMS studies suggested hydrolysis, hydroxylation, dehydration, O-methylation, hydroxylation and/or the reduction of hydrolyzed derivatives, depending on the concentration and the position of the ester link. Further permeability and absorption studies are required to better define triterpenic esters pharmacokinetic and specific formulations designed to increase their oral bioavailability.

In Vitro and in Vivo Antigen-Induced Release of High-Molecular Weight Neutrophil Chemotactic Activity from Human Nasal Tissue

1988 ◽  
Vol 2 (1) ◽  
pp. 7-11 ◽  
Author(s):  
T. Nagakura ◽  
T. Onda ◽  
Y. likura ◽  
T. Endo ◽  
H. Nagakura ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Nasal Polyps ◽  
Gel Filtration ◽  
Chemotactic Activity ◽  
Nasal Tissue ◽  
Nasal Secretions ◽  
Neutrophil Chemotactic Activity

High molecular weight neutrophil chemotactic activity has been identified in resected human nasal polyps, inferior turbinates, and nasal secretions following antigen challenge. The estimated molecular weight, by gel filtration chromatography, was approximately 600,000. However, a heterogeneity of molecular weight in some patients was recognized. Our results suggest a possible role for high molecular weight-neutrophil chemotactic activity in the pathogenesis of hypersensitivity in the human nasal cavity.

The Fibrin Assay Comparison Trial (FACT)

2001 ◽  
Vol 85 (04) ◽  
pp. 671-678 ◽  
Author(s):  
Sybille Zips ◽  
Hanimsah Ergül ◽  
Dieter Heene ◽  
Carl-Erik Dempfle ◽  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Degradation Products ◽  
Plasma Samples ◽  
Fibrin Degradation Products ◽  
Comparison Trial ◽  
Clinical Conditions ◽  
D Dimer

SummaryAlthough D-dimer has gained widespread clinical use as a parameter for detection of in vivo fibrin formation, the issue of standardization of D-dimer assays remains to be resolved. The FACT study was performed to generate basic data for development of calibrators and standard preparations.A set of 86 samples, including plasma samples from patients with DIC, DVT, and other clinical conditions, serial dilutions of pooled plasma samples, and plasma samples containing fibrinogen- and fibrin derivatives, were distributed to 12 manufacturers of D-dimer assays.D-dimer assays differ concerning specificity for crosslinked fibrin, and preference for either high molecular weight fibrin complexes, or low molecular weight fibrin degradation products. Terminal plasmin digests of fibrin clots for calibration produce aberrant results in some assays, especially those with preference for high molecular weight crosslinked fibrin derivatives. The best conformity is achieved by the use of pooled plasma samples from patients with high levels of D-dimer antigen in plasma. In vitro preparations containing a comparable composition of fibrin derivatives to clinical plasma samples may also serve as reference material.

Fibrin-I Degradation Products with a Molecular Weight Higher than That of Fibrinogen

1973 ◽  
Vol 29 (01) ◽  
pp. 122-129 ◽  
Author(s):  
René von Hugo ◽  
Henner Graeff
Keyword(s):  
Molecular Weight ◽  
Gel Electrophoresis ◽  
Degradation Products ◽  
Gel Filtration ◽  
Agarose Gel ◽  
Two Dimensional ◽  
Plasma Clot ◽  
Two Dimensional Gel Electrophoresis ◽  
Parent Molecule

SummaryThe observation of intravascular lysis of fibrin deposits and of fibrinogen derivatives with a molecular weight higher than the parent molecule in human cases of disseminated intravascular coagulation (DIC) initiated the following in vitro study. Following streptokinase induced plasma clot solubilization fibrinogen derivatives were investigated after ß-alanine precipitation of the plasma samples by polyacrylamide (PAA) gel electrophoresis, intra gel immunoprecipitation, two dimensional gel electrophoresis and by agarose gel filtration. Three fibrin-i degradation products were observed and characterized according to their relative electrophoretic mobility in 5% PAA gel: 0.23, 0.35, 0.46 (fibrinogen: 0.43) x 10-5 cm2/V x sec. They could also be demonstrated after electrophoresis in the presence of 5 M urea. Agarose gel filtration yielded one peak at 180 ml of effluent volume. The 0.23 derivative was eluted in the peak fractions, whilst the 0.35 and 0.46 derivatives were eluted together at approximately 201 ml of the effluent volume (fibrinogen: 225 ml). This indicates, that the three fibrin-i degradation products described are molecular entities with molecular weights higher than fibrinogen and, that the 0.46 derivative has an increased charge/molecular size ratio in comparison with fibrinogen. Corresponding data were obtained by two dimensional gel electrophoresis in gels of different pore size.

scholarly journals Fibrin and fibrinogen degradation products with an intact D-domain C- terminal gamma chain inhibit an early step in accessory cell-dependent lymphocyte mitogenesis

Blood ◽  
1993 ◽  
Vol 81 (11) ◽  
pp. 3006-3014 ◽  
Author(s):  
SC Robson ◽  
R Saunders ◽  
LR Purves ◽  
C de Jager ◽  
A Corrigall ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Degradation Products ◽  
Specific Binding ◽  
Lymphocyte Transformation ◽  
Mononuclear Leukocytes ◽  
Accessory Cell ◽  
Binding Studies ◽  
Gamma Chain

Abstract Although the low molecular weight degradation products of fibrinogen (FgDP) and fibrin (FbDP) are known to inhibit lymphocyte blastogenesis, the effect of purified macro-molecular FgDP and FbDP (molecular weight, 90 to 200 Kd) is unclear. We have examined the effect of these latter FgDP and FbDP and find that products that contain the D domain inhibit lymphocyte proliferation in response to T-cell mitogens, allogeneic mononuclear leukocytes, and anti-CD3 in vitro. Plasmic digestion of D1 in the absence of calcium with removal of the C-terminal end of the gamma chain or disruption of the gamma-gamma C-terminal cross-link site of D-dimer (DD) by puffadder venom (PAV-D) abrogates their inhibitory potential. Prior incubation of monocytes with DD or D1 inhibits subsequent lymphocyte transformation. Binding studies with radiolabeled DD and PAV-D confirm that monocytes interact only with DD. This specific binding may be competitively inhibited by monoclonal antibodies to CD11b/CD18 or by peptide analogues of the C-terminal gamma chain of fibrinogen that mimic the adhesion recognition site of integrins. We postulate that DD and D1 bind to CD11b/CD18 on adherent monocytes and modulate lymphocyte activation. These products are typically present in the plasma of patients with disseminated intravascular coagulation with sepsis and could therefore influence inflammatory processes in vivo.

Distribution of radioactive silver in the subcellular fractions of various tissues of the rat and its binding to low molecular weight proteins

1983 ◽  
Vol 61 (11) ◽  
pp. 1391-1395 ◽  
Author(s):  
Yousef Matuk
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Gel Filtration ◽  
Total Radioactivity ◽  
Subcellular Fractions ◽  
Low Molecular Weight ◽  
Electron Microscopic ◽  
Molecular Weight Peak

In view of the electron microscopic evidence that silver does not penetrate cellular barriers, the distribution of radioactive silver in rat blood and subcellular fractions of liver, kidneys, spleen, and forebrain was studied. It was found that 24 h after a single intraperitoneal injection high levels of radioactivity were reached which decreased at different rates in the various tissues studied. In plasma, liver, and kidneys there was an initial rapid loss of radioactivity which was followed by a slower rate of loss. In the blood, forebrain, and spleen the loss of radioactivity was linear and somewhat slower than in the other three tissues. The cytosols of the liver and kidneys contained 60% while those of the forebrain and spleen contained 30% of the total radioactivity found in the tissue homogenates. Gel filtration on Sephadex G-75 showed that all cytosols contained two peaks of radioactivity; a high molecular weight peak which eluted just after the void volume and a low molecular weight peak. The amount of radioactivity in both peaks was, however, much lower in the chromatographic peaks of the forebrain and spleen than that found in those of the liver and kidneys. Furthermore, the spleen had a comparatively very small low molecular weight radioactive peak. In vitro experiments with liver cytosol showed similar results to those found in vivo in that the high molecular weight radioactive peak could be removed by heat. It is concluded that silver does enter cells and that silver thionein exists in the cytosols of forebrain, spleen, kidney, and liver.

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